Removal of shoot tips is a very useful technique to boost the production of tea leaves. This is because:
| 1. | Gibberellins prevent bolting and are inactivated. |
| 2. | Auxins prevent leaf drop at early stages. |
| 3. | Effect of auxins is removed and the growth of lateral buds is enhanced. |
| 4. | Gibberellins delay the senescence of leaves. |
One scientist cultured Cladophora in a suspension of Azotobacter and illuminated the culture by splitting light through a prism. He observed that bacteria accumulated mainly in the region of:
| 1. | Violet and green light | 2. | Indigo and green light |
| 3. | Orange and yellow light | 4. | Blue and red light |
In order to increase the yield of sugarcane crops, which of the following plant growth regulators should be sprayed?
| 1. | Ethylene | 2. | Auxins |
| 3. | Gibberellins | 4. | Cytokinins |
What type of pollination takes place in Vallisneria?
| 1. | Pollination occurs in submerged conditions by water. |
| 2. | Flowers emerge above the surface of water and pollination occurs by insects. |
| 3. | Flowers emerge above the water surface and pollen is carried by the wind. |
| 4. | Male flowers are carried by water currents to female flowers at the surface of the water. |
In which one of the following, both autogamy and geitonogamy are prevented?
1. Wheat
2. Papaya
3. Castor
4. Maize
Match the placental types Column-I with their examples Column-II.
| Column-I | Column-II | ||
| (a) | Basal | (i) | Mustard |
| (b) | Axile | (ii) | China rose |
| (c) | Parietal | (iii) | Dianthus |
| (d) | Free central | (iv) | Sunflower |
Choose the correct answer from the following options:
| Options: | (a) | (b) | (c) | (d) |
| 1. | (ii) | (iii) | (iv) | (i) |
| 2. | (i) | (ii) | (iii) | (iv) |
| 3. | (iv) | (ii) | (i) | (iii) |
| 4. | (iii) | (iv) | (i) | (ii) |
A selectable marker is used to:
| 1. | help in eliminating the non-transformants so that the transformants can be regenerated. |
| 2. | identify the gene for the desired trait in an alien organism. |
| 3. | select a suitable vector for transformation in a specific crop. |
| 4. | mark a gene on a chromosome for isolation using a restriction enzyme. |
Western Ghats have a large number of plant and animal species that are not found anywhere else. Which of the following terms will you use to notify such species?
| 1. | Endemic | 2. | Vulnerable |
| 3. | Threatened | 4. | Keystone |
Which of the following statements about ozone is correct?
1. Tropospheric ozone protects us from UV radiation
2. Stratospheric ozone is 'bad'
3. Tropospheric ozone is 'good'
4. Stratospheric ozone protects us from UV radiation